Abstract
Pythium red blight is one of important diseas of bent grass, and is caused by infection of Pythium aphanidermatum. IAA, linoleic acid and P-hydroxybenzaldehyde were isolated from the metabolite of Pythium aphanidermatum. IAA and linoleicacid completely inhibited tea pollen tube gowth at a concentration of 100mg/l. IAA inhibited the hypocotyl elongation and the root growth of lettuce seedlings by 13% and 8% at a concentration of 100mg/l. However, IAA, linoleicacid and p-hydroxybenzaldehyde showed no inhibitory activity against the growth of rice seedlings at the sama concentration. IAA completely inhibited the growth of bent grass at a concentration of 1000mg/l.On the other hand, linoleic acid and p-hydroxybenzaldehyde did not show any remarkable inhibitory activity against the gowth of bent grass at the same concentration.
